Line of Credit Facility, Extension Period

No definition available.

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Namespace Prefix:	gm_
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Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of increase (decrease) of the credit facility.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period.

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Debt - Secured Debt and Unsecured Debt (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended	12 Months Ended
	Sep. 30, 2021	Apr. 30, 2021	Dec. 31, 2021	Dec. 31, 2021	Jan. 31, 2022	Mar. 31, 2021	Dec. 31, 2020
Automotive
Debt Instrument [Line Items]
Weighted-average interest rate on outstanding long-term debt			5.80%	5.80%			5.60%
Revolving Credit Facility \| GM Financial \| Unsecured Debt
Debt Instrument [Line Items]
Weighted-average interest rate			2.69%	2.69%
Maximum \| Revolving Credit Facility \| GM Financial \| Unsecured Debt
Debt Instrument [Line Items]
Debt term				4 years
Line of Credit \| Unsecured Debt
Debt Instrument [Line Items]
Aggregate borrowing capacity		$ 11,200
Line of Credit \| Unsecured Debt \| Five Year Revolving Credit Facility Due 2023
Debt Instrument [Line Items]
Debt term		5 years	5 years
Aggregate borrowing capacity						$ 10,500
Line of Credit \| Unsecured Debt \| Five Year Revolving Credit Facility Due 2026
Debt Instrument [Line Items]
Debt term		5 years
Aggregate borrowing capacity		$ 9,900
Line of credit extension period		3 years
Line of Credit \| Unsecured Debt \| Three Year Revolving Credit Facility April 2021
Debt Instrument [Line Items]
Debt term				3 years
Aggregate borrowing capacity			$ 4,000	$ 4,000
Line of Credit \| Unsecured Debt \| Three Year Revolving Credit Facility April 2024
Debt Instrument [Line Items]
Debt term		3 years
Aggregate borrowing capacity		$ 4,300
Line of Credit \| Unsecured Debt \| $2.0 Billion Dollar Revolving Credit Facility
Debt Instrument [Line Items]
Debt term			364 days
Aggregate borrowing capacity			$ 2,000	$ 2,000
Line of Credit \| Automotive \| Unsecured Debt \| $2.0 Billion Dollar Transformation Facility Due January 2022
Debt Instrument [Line Items]
Debt term				3 years
Aggregate borrowing capacity			2,000	$ 2,000
Line of Credit \| GM Financial \| Unsecured Debt \| $2.0 Billion Dollar Revolving Credit Facility
Debt Instrument [Line Items]
Debt term		364 days		364 days
Aggregate borrowing capacity		$ 2,000	$ 2,000	$ 2,000
Line of Credit \| Revolving Credit Facility \| GM Financial \| Secured Debt
Debt Instrument [Line Items]
Increase to maximum borrowing capacity				$ 25,800
Senior Notes \| Unsecured Debt
Debt Instrument [Line Items]
Repayments of debt	$ 450
Senior Notes \| GM Financial \| Subsequent Event
Debt Instrument [Line Items]
Amount of debt issued					$ 2,600
Weighted-average interest rate					2.57%
Senior Notes \| GM Financial \| 5.2% Senior Notes Due March 2023
Debt Instrument [Line Items]
Amount of debt issued	$ 1,500
Stated interest rate	5.20%
Loss on extinguishment of debt	$ 105
Senior Notes \| GM Financial \| Unsecured Debt
Debt Instrument [Line Items]
Weighted-average interest rate on outstanding long-term debt			2.77%	2.77%
Amount of debt issued			$ 12,200	$ 12,200
Weighted-average interest rate			1.62%	1.62%
Notes Payable, Other Payables \| GM Financial \| Secured Debt \| Securitization notes payable
Debt Instrument [Line Items]
Weighted-average interest rate on outstanding long-term debt			1.27%	1.27%
Amount of debt issued			$ 23,300	$ 23,300
Weighted-average interest rate			0.79%	0.79%